A temperature-control unit is described in US 2008/0060792 A1. Said cooling device consists of a housing which can be placed for example onto an electronic component that is to be cooled. The surface to be cooled of this electronic component forms, together with the housing, a cavity into which a cooling fluid consisting of a liquid and an admixed gas can be introduced. Use is made in this case of a nozzle which is directed towards the surface to be cooled of the component. The fluid can exit the temperature-control unit again through an outlet.